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The changing climate is closely related to changes in the bioclimate. This research deals with the present bioclimate and its projected evolution over the entirety of the natural and agricultural lands of south-eastern Europe and individual countries (Bulgaria, Greece, Kosovo, N. Macedonia, Romania, and Serbia). For this purpose, an ultrahigh spatial resolution of the de Martonne bioclimatic index pattern was elaborated and analysed for the first time. The survey is performed over the reference period (1981–2010) and future time frames (2011–2040; 2041–2070; 2071–2100) under SSP370 and SSP585 emission scenarios. On a territorial level, both natural and agricultural areas appear as highly impacted by the future changes of bioclimate; the highest xerothermic trend is expected to influence the latter areas, mostly in 2071–2100 and under the higher emission scenario. The natural areas will face an expansion in the semidry class from 0.9% (of the total area) during the reference period to 5.6% during 2071–2100 under the RCP8.5 scenario as the dominant extremely humid class falls from 53.5% to 32.9% for the same periods and scenario. On the other hand, agricultural areas will face a more intense xerothermic alteration going from 4.9% to 17.7% for the semidry class and from 41.1% to 23.5% for the dominant very humid class for the same periods and scenario. This study presents the spatial statistics per country for the selected scenarios and periods to provide information for stakeholders. This study's results highlight the necessity for intensifying adaptation plans and actions aiming at the feasibility of agricultural practices and the conservation of natural areas. [ABSTRACT FROM AUTHOR]

Light availability and its composition in components affecting plant growth as photosynthetically active radiation (PAR), are of critical importance in agricultural and environmental research. In this work, radiation data for the period 2009–2014 in a forest site in Greece were analyzed to identify the effect of meteorological variables on the formation of the photosynthetically active to global solar radiation ratio. The temporal changes of the ratio are also discussed. Results showed that the ratio values are higher in summer (0.462) and lower in autumn (0.432), resulting in an annual average of 0.446. In addition, for the investigated site, which was characterized by relatively high water content in the atmosphere, the atmospheric water content and clearness were found to be the most influential factors in the composition of the global solar radiation in the wavelengths of PAR. On the contrary, temperature and related meteorological attributes (including relative humidity, vapor pressure deficit and saturation vapor pressure) were found to have minor effect. [ABSTRACT FROM AUTHOR]

The aim of this study was to characterize the prevalence and seasonal variation of vitamin D (vit D) deficiency/insufficiency in healthy children and adolescents in Greece, and to explore its relationship with the use of sunscreens. The serum level of 25-hydroxy-vitamin D (25(OH)D) was measured in 376 children and adolescents (184 males and 192 females) with a mean age of 7.6 ± 4.9 years, at different time points over a period of 13 months. The prevalence of low serum 25(OH)D level, including deficiency and insufficiency, was 66.2%. The lowest mean 25(OH)D was observed in the month of January (17.9 ± 6.8 ng/mL) and the highest in September, July, August, and October (34.6 ± 8.7, 33.0 ± 9.4, 30.1 ± 8.2, and 30.1 ± 10.6 ng/mL, respectively). Higher levels of serum 25(OH)D were detected in the children to whom sunscreens had been applied on the beach (p = 0.001) or off the beach (p < 0.001). The subjects with deficiency and insufficiency were significantly older than those with normal levels of 25(OH)D, but no significant differences were demonstrated according to gender. This study emphasizes the high prevalence of low serum levels of 25(OH)D and their seasonal variation in children living in a region characterized by many hours of sunshine. Our data suggest that the real-life use of sunscreens during the summer months allows sufficient sunlight to be received to enable production of vit D at a level adequate to maintain normal serum levels. Vit D supplements should be given to children during the months of lower sun exposure. [ABSTRACT FROM AUTHOR]

This work deals with the assessment of the outdoor environment of a sanatorium site in mountainous conditions which were historically considered favourable in the treatment of tuberculosis patients in the pre‐antibiotic era. Thermal climate conditions are estimated through application of the thermal climate index (THI) to site‐specific air temperature and relative humidity data along with kata‐thermometer data recorded at the balconies outside of patients' rooms. Results show that the cold conditions dominate throughout the winter period at all observation times, whereas conditions of comfort prevail during summer, in morning and evening hours, and occur frequently in spring and autumn at noon. [ABSTRACT FROM AUTHOR]

Annual fish landings for the Greek seas were analysed for the period 1982-2007 and classified into exploitation categories based on a catch-based stock classification method. In 2007, about 65% of the Greek stock were characterised as overfished, 32% as fully exploited and only 3% were characterised as developing; collapsed stocks were not recorded. The cumulative percentage of fully exploited and overfished stocks has been increasing over the past 20 years suggesting overexploitation of resources. The results were contrasted against total landings, the fishing-in-balance index ( FiB) and fishing effort, and some irregularities on the dataset were explained based on current legislation and management measures. A positive correlation between FiB and total fishing effort confirmed the expansion of the Greek fisheries up to 1994, but contraction thereafter. The results suggest that the apparently stable overall catches and decreasing effort may be deceiving, as they hide an underlying pattern of overexploitation in some of the stocks. It was concluded that the Greek fisheries are no longer sustainable and radical management measures are needed. [ABSTRACT FROM AUTHOR]

Abstract: This work investigates how to reduce, by appropriate urban design, air temperature at the street level and to improve pedestrian thermal conditions in summer. The case study is a street in Athens with low aspect ratio H/W (H: building height; W: street width), low trees canopy coverage level, and high traffic. Urban variables for design are trees canopy coverage area ratio, traffic load, walls surfaces albedo, and H/W. Their thermal effect is separately and altogether estimated by applying the microclimatic Green-CTTC model whereas thermal stress is assessed using the Physiological Equivalent Temperature (PET) index. The studied day is relatively hot (36.5 °C at midday) with eight hours of heat stress (two and six hours of extreme and strong heat stress, respectively) at street level. Acceptable near-to-discomfort limits for local pedestrians are considered whereas PET classification heat stress levels are adjusted to local conditions by applying a correction equation to obtained PET values. Results show that the examined scenarios are associated with air temperature decrease and improvement of thermal comfort in the shade, especially during the day''s hottest hours. The trees thermal effect is the dominant factor followed by the increase of H/W and of the walls surfaces albedo. All the studied design scenarios are found able to reduce the number of heat stress hours but the trees canopy coverage area ratio increase scenario was found by itself able to be associated only with moderate heat stress for local pedestrians. Alternative local smart controls for thermal comfort (SCAT) options are also discussed. [Copyright &y& Elsevier]

Introduction: Renal nurses should have counselling and communication skills with patients, to deal with stressful situations at work. A prerequisite for the acquisition of these skills is renal nurses' self-knowledge. This study aims to present the effectiveness of an ongoing training program to renal nurses related to self-esteem. Methodology: A quasi experimental research, which has a theoretical background from the Rational- Emotive Behaviour Therapy of A. Ellis and from the transformative learning of J. Mezirow. The program attended 31 renal nurses working in district hospitals. Results: During evaluation of the training activity it was quite successful at the cognitive effect that occurred to the participants. In emotional and in behavioural level, almost 80% of participants improved their attitude towards the absurd ideas that formed their self-esteem by 90%. Conclusion: All who attended the program improved their attitude regarding their absurd ideas-beliefs, something that reduced person's self-esteem, making further negative consequences for their psychosomatic health. [ABSTRACT FROM AUTHOR]

Abstract: The present work investigates the causes of the variability in air temperature patterns among urban streets with trees in Athens, as obtained from in situ measurements, in a suburb area and in the city center. Urban variables studied are: the extent of tree canopy coverage, traffic load, surfaces albedo modification, street deepening aspect and the street’s ventilation. The thermal effect of each variable is estimated by simulations using the Green CTTC analytical microclimate model. The model was first validated with measurements data and consequently used to study the effect of the various urban variables in attenuating the high values of air temperature within the studied streets considering two feasible scenarios for each of the examined streets. Model results revealed that the total attenuation effect in reducing the air temperatures inside the streets may reach as much as 5 K at noontime with a daily average cooling of 3 K. Further, the study demonstrates the potential use of microclimate modeling in assessing the merits of proposed passive cooling strategies in urban streets. [ABSTRACT FROM AUTHOR]

Abstract: Air temperature measurements under the vegetation canopy of trees in suburban streets and at reference points were carried out under mostly light wind conditions in five streets in the city of Athens (Greece) during a short exceptionally hot weather period in 2007. The average cooling effect at 1400 h (LST) was found to range from 0.5 to 1.6 °C and at 1700 h (LST) from 0.4 to 2.2 °C; the highest cooling effect of 2.2 °C was found to be reached in a street with high tree shaded area and minimal traffic load. These results imply the passive cooling potential of shade trees. The trees cooling effect values obtained for Athens, however, were found to be lower than the ones reported in similar studies in the Mediterranean region. In terms of residential energy implications, the elaboration of the results using simplified assumptions showed that the current level of tree cover in the examined streets may reduce summer time consumption for air conditioning during the day by 2.6–8.6% and during peak hours by 2.9–9.7%. [Copyright &y& Elsevier]

The present study deals with the development and application of Artificial Neural Network (ANN) models as a tool for the evaluation of human thermal comfort conditions in the urban environment. ANNs are applied to forecast for three consecutive days during the hot period of the year (May-September) the human thermal comfort conditions as well as the daily number of consecutive hours with high levels of thermal discomfort in the great area of Athens (Greece). Modeling was based on bioclimatic data calculated by two widely used biometereorogical indices (the Discomfort Index and the Cooling Power Index) and microclimatic data (air temperature, relative humidity and wind speed) from 7 different meteorological stations for the period 2001-2005. Model performance showed that the risk of human discomfort conditions exceeding certain thresholds can be successfully forecasted by the ANN models. In addition, despite the limitations of the models, the results of the study demonstrated that ANNs, when adequately trained, could have a high applicability in the area of prevention human thermal discomfort levels in urban areas, based on a series of relatively limited number of bioclimatic data values calculated prior to the period of interest. [ABSTRACT FROM AUTHOR]

A new methodological approach is presented for quantifying the meteorological effects on cotton production during the growing season in Greece. The proposed Bhalme and Mooley Vegetation Condition Index (BMVCI) is based on the Vegetation Condition Index (VCI) extracted by National Oceanic and Atmospheric Administration (NOAA) Advanced Very High Resolution Radiometer (AVHRR) data. In this approach the VCI data is processed with the Bhalme and Mooley methodology to assess the accumulated meteorological effects on cotton from April to August. The resulting index is at the same scale as the Z-Index, which is the classification of the Palmer Drought Severity Index (PDSI) extensively used for drought monitoring. For this study 16 years of data are examined to illustrate that the weather development as identified from satellite data with the use of BMVCI confirm unfavourable conditions for cotton production. For the validation of BMVCI an empirical relationship between the cotton production and the BMVCI values is derived. The resultant high correlation coefficient refers to very encouraging results and confirms the usefulness of the proposed integrated methodological approach as an effective tool for early assessment of the cotton production in Greece. [ABSTRACT FROM AUTHOR]

Satellite data can significantly contribute to agricultural monitoring. The reflected radiation, as recorded by satellite sensors, provides an indication of the type, density and condition of canopy. A widely used index for vegetation monitoring is the Normalized Difference Vegetation Index (NDVI) derived from the National Oceanic and Atmospheric Administration/Advanced Very High Resolution Radiometer (NOAA/AVHRR) data provided in high temporal resolution. An extension of the NDVI is the Vegetation Condition Index (VCI). VCI is a tool for monitoring agrometeorological conditions, providing a quantitative estimation of weather impact to vegetation. The primary objective of this paper is the quantitative assessment of the cotton yield before the end of the growing season by examining the weather effects as they are depicted by the VCI. The study area comprises several cotton producing areas in Greece. Ten-day NDVI maximum value composites (MVC) are initially utilized for the period 1982-1999. The correlation between VCI images as extracted from NDVI and the 10-day intervals during the growing season is examined to identify the critical periods associated mostly with the yield. Empirical relationships between VCI and yield are developed. The models are tested on an independent dataset. The results show that an early estimation of the cotton yield trend is feasible by the use of the VCI. [ABSTRACT FROM AUTHOR]

Potential evapotranspiration (PET) is a key parameter for climate classification and aridity assessment. The widely used UNEP (1992) classification system is based on the estimation of the aridity index AI, which requires annual average values of precipitation P and PET. For the calculation of PET the Thornthwaite's (1948) formula is, in principle, suggested. Recent studies use more advanced and accurate methods for PET estimation but apply to AI the same thresholds proposed by UNEP for aridity classification. This work deals with the uncertainties introduced by the use of different PET methods in the estimation of the aridity index AI. Specifically, the Hargreaves-Samani (HS) method and four of its modifications, three modifications of Thornthwaite's formula and the equation of Hamon, are evaluated against the widely used Thornthwaite's original method, by assessing their impact on the AI. Climatic data as monthly average values of at least 30 years of measurements from 122 stations in the Greek peninsula are used. Results show that AI is highly affected by the PET method adopted, resulting thus to changes in climatic classification of a region. Further, results imply the need for an adjustment of the threshold values that determine aridity classes according to the method each time adopted. Therefore, new threshold values for the aridity classes are developed and presented in this work. The proposed threshold values cover a range of sites that belong to semi-arid SA, sub-humid SH and humid H aridity classes of the Greek peninsula. • UNEP Aridity Index AI is highly affected by the PET method adopted for its estimation. • 10 PET methods effect on AI is assessed for 122 sites over the Greek peninsula. • Uncertainty in aridity classification under Mediterranean climatic conditions. • Most sites were categorized to more arid classes compared to Thornthwaite's approach. • AI adjustment coefficients and threshold values are proposed for each PET method. [ABSTRACT FROM AUTHOR]

This study assessed vitamin D status in asymptomatic children and adolescents in Greece, with and without atopy, and possible changes during the coronavirus disease 2019 (COVID-19) pandemic. Serum levels of 25-hydroxy-vitamin D (25(OH)D) and total immunoglobulin E (IgE), and eosinophil count were measured in 340 asymptomatic children and adolescents (155 males, 185 females), mean age 8.6 ± 4.6 years, recruited over a period of 24 months (February 2019–January 2021). Atopy, defined by high level of IgE for age, was associated with vitamin D deficient status (p = 0.041). Subjects with and without atopy showed similar rates of insufficient and normal levels of 25(OH)D. The median level of 25(OH)D was significantly higher in subjects recruited during the pandemic, when home confinement rules were observed, than before the pandemic, and significantly more children had normal levels of 25(OH)D (p < 0.001), but no differences were noticed for IgE levels or eosinophil count. These results support a link between vitamin D and allergic and infectious inflammations, and specifically the association of vitamin D deficiency with asymptomatic atopy, defined as increased IgE level for age. [ABSTRACT FROM AUTHOR]

The temporal variability of the aridity index (AI) in Greece is examined over an almost century period (1900–1997) and for a number of meteorological stations according to data availability. The analysis is carried out for three distinct climatic periods: 1900–1929, 1930–1960 and 1961–1997. In addition to the use of AI, other drought related parameters based on Thornthwaite's water budget approach are adopted to provide more insights into the variability of AI. Results show a relatively slow but steadily progressive establishment of drier conditions in most areas. During the early climatic period most of the totally 25 examined areas in the Greek peninsula are classified as 'Humid' with a few exceptions for the 'Sub-Humid' class and for the 'Semi-Arid' class'. Within the second examined period, a shift from the 'Sub-humid' class towards the 'Semi-Arid' class appeared mostly in the Aegean Sea Cyclades Islands. The most significant shift was found to appear during the third period with changes from the 'Humid' class to the 'Sub-humid' class in parts of the continental Greece, in Eastern Crete and in mountainous areas. In some areas (e.g. Attica basin) AI values tend to approach the threshold value for shift from the 'Semi-Arid' class to the 'Arid' class whereas for a number of areas located in the western coastal region, the AI class 'Humid' remains unchanged during all three periods. • A relatively slow but steadily progressive establishment of drier conditions in most areas occurs • A shift from 'Sub-humid' towards 'Semi-Arid' class appeared in the Aegean Sea Cyclades during 1930–1960 • The most significant shift ('Humid' to 'Sub-humid') was found to appear during 1961–1997 • Some continental areas tend to approach the threshold index value for shift from 'Semi-Arid' to 'Arid' • Some areas in the western coastal region maintain the Humid class unchanged during all climatic periods [ABSTRACT FROM AUTHOR]

Elaborates the application of parametric and nonparametric models to the assessment of fluoride levels in vegetation exposed to stack emissions of an aluminum reduction plant in Greece. Advantages of using a linear statistical model for the assessment of airborne fluoride levels in natural vegetation; Evaluation of results obtained as a result of use of artificial neural networks on the same experiment; Comparative benefits of linear models over multimedia-based simulations.

Abstract: This study proposes an innovative approach for investigating the accumulated meteorological effects on cotton during the growing season. The quantification of the weather effects is based on the application of the Bhalme and Mooley drought index (BMDI) methodology on the vegetation condition index (VCI) extracted by NOAA/AVHRR data. The resulted Bhalme and Mooley vegetation condition index (BMVCI) is in the same scale as the Z-index, as proposed in the Palmer drought severity index (PDSI) for drought monitoring. The study area comprises the region of Thessaly, which is the most cotton productive area in Greece. Eighteen years of NOAA/AVHRR data are examined and processed with the BMVCI to examine the unfavorable conditions for cotton production. For the validation of BMVCI an empirical relationship between the cotton production of Thessaly and the BMVCI values is derived for the period 1982–1997. The methodology is validated for the two following years (1998 and 1999). The estimated cotton production approximates 5% and 2%, respectively, the real values for the validated years. The results confirm the usefulness of this integrated methodological approach as an effective tool to assess cotton production in Thessaly. [Copyright &y& Elsevier]

Photosynthetically active (PAR) and ultraviolet-A (UVA) radiation have important effects on plant processes, affecting both health and ecology of the natural ecosystems. Studies dealing with the composition of global solar radiation Rs in PAR and UVA wavelengths are thus important. The present work is aimed at the investigation of the relationships of PAR, UVA with Rs, assessing the key factors that affect the corresponding ratios PAR/Rs and UVA/Rs at a high-altitude mountainous environment. The study was conducted in a protected Natura-2000 forest in Greece at a high altitude (1896 m a.s.l.) site and covers a time period of about 5 years (2014–2019). The analysis was performed on a monthly, seasonal and annual basis using hourly data. Results show that PAR/Rs and UVA/Rs present annual values 0.438 ± 0.031 and 0.034 ± 0.007, respectively with low monthly and seasonal variability. Further, sky clearness was found to have a significant effect on the composition of incident Rs, with PAR/Rs values to increase from 0.417 ± 0.013 to 0.483 ± 0.037 as sky conditions change from clear to overcast. The respective UVA/Rs values were 0.031 ± 0.002 and 0.045 ± 0.011. The hourly ratios become minimum at noon, whereas the magnitude of Rs was found to have a negative effect. In addition, PAR/Rs and UVA/Rs were increasing with relative humidity, optical thickness and relative optical air mass and decreasing with saturation vapor pressure, vapor pressure deficit, and to a less degree with air temperature. Concluding, at the high altitude Mediterranean forest site, Rs composition to PAR and UVA appears to be affected mainly by atmospheric clearness and by the geometric characteristics of the incident radiation rays, whereas atmospheric clearness was affected mainly by air humidity. • PAR/Rs and UVA/Rs were investigated on a high altitude-unpolluted Mediterranean forest. • The radiation ratios are determined by the atmospheric clearness. • Cloud cover and/or increased air humidity lead to increased PAR/Rs and UVA/Rs values. • The radiation ratios are not considerably affected by air temperature. • Sun's position and rays path length in the atmosphere highly affect the radiation ratios. [ABSTRACT FROM AUTHOR]